The primary question regarding spinner

Hi Guys
I am a "maxscript" beginner. I just want to do an exercise. I want to "outline" in the"editable spline" feature extracted. A button, a spinner, a checkbox named center.But I do not know how they are linked. macrorecorder can't feedback property of outline spinner and checkbox named center.Of course, there are a lot of similar questions.for example : "weld spinner" "fillet spinner" "chamfer spinner"......... I really searched for maxscript reference ,but .......
The "weld" in Editable Poly have ".weldThreshold" but Editable spline have "????"
Can you help me ?
My English not very good you know what I mean??????